London police are questioning two men arrested late Monday in connection with the attempted bombing of the city's transport system 12 days ago. There are 17 suspects being held in the plot to blow up three subway trains and a bus.

London transport authorities have re-opened two subway lines that were closed following the July 7 bombings that killed 52 passengers and four British Muslim suicide bombers in the capital's deadliest-ever terrorist attacks.

Bomb-weary London commuters are welcoming the restoration of service on the District and Hammersmith and City lines, though the heavily used Piccadilly and Circle lines remain cut because of damage from the July 7 blasts.

But even as public transport gets back to normal, a new controversy has erupted over a police policy to stop and search young Muslim commuters carrying suspicious bags.

The July 7 bombings were carried out by four British Muslim men aged between 18 and 30. Police say three were of Pakistani background, and one was born in Jamaica.

Three of the prime suspects identified in the July 21 attempted bombings are Muslims in their 20s who were born in East Africa. The age and birthplace of a fourth suspect has not been revealed.

British Transport Police Chief Constable Ian Johnston says that given those profiles, it would be fruitless for his officers to stop what he describes as "little old white ladies."

British Home Office Minister Hazel Blears is trying to calm the concerns of Muslims that they are being picked on, as she explained in an interview with British radio.

"Stop-and-search is there to be used on the basis of the intelligence that is available about the threat that is facing us," she said. "It should not be used against any particular community. I mean, just picking people up on the basis of them being Muslim is never going to get the result that you want."

Her appeal for more cooperation from the Muslim community to root out terrorists in their midst is not being well received in all quarters.

"It is not the Muslim community's position to take it upon themselves to be the local policemen," said Sahid McBool, an editor of a magazine called Revival, which is aimed at young British Muslims. "If the government really wants to get the help of the Muslims it should stop blaming the Muslims for these atrocities that have nothing to do with Islam."

In a separate development, Home Office Minister Blears says Britain expects the speedy extradition of one of the accused would-be bombers who was arrested in Rome last week.

She says there are no Italian charges against the man, Hamdi Issac, contradicting his lawyer who says he faces legal charges of links to international terrorism and possession of false identity papers.